Following last week's Wild West adventure, this week's Doctor Who episode is something rather out of the ordinary - Chris Chibnall's 'The Power of Three' charts the year of the slow invasion...

It's time to take a look at the world of the Doctor (Matt Smith) through the eyes of his companions Amy (Karen Gillan) and Rory (Arthur Darvill) one last time before the pair depart for good the following Saturday.